Process and apparatus for disintegration of material



Aug. 15, 1933. w; MASON 1,922,313

PROCESS AND APPARATUS FR DISINTEGRA'I'ION OF MATERIAL Filed June 27, 1931 2 Sheets-Sheet l INVENTOR Will tam H Mason ATTORNEYS W. H. MASON Aug. 15, 1933.

PROCESS AND APPARATUS FOR DISINTEGRA'IION OF MATERIAL Filed June 27, 1931 2 Sheets-Sheet 2 INVENTOR Will 12am H Mason BY 19 M ATT RNEYS Patented Aug. 15, 1933 A UNITED STATES PATENT OFFICE PROCESS APPARATUS FOR DISINTE- GRATION OF MATERIAL William ll. Mason, Laurel, Miss., assignor Masonite Corporation, Laurel, Miss. a Corporation of Delaware Application June 2'1, 1931. Serial No. 547,259

31 Claims. (Cl. 92-1) My invention relates to an improved process Separated y time intervals t it has been and apparatus for the fibration or disintegration imp a t c b to a pt to u e t d sc a g d of variousmaterials. The invention may be used esgeeping Steemfor-disintegrating a great variety of materials, The present invention has for its main j t 5 and the particular material which is described to Provide a Process d apparatus which y herein is ligno-cellulose, for example wood chips Preference Operates Continuously With the dvenand the like. The material to be treated such tage of yielding an increased u p w th a eas wood-chips or other porous material in parduction in labor, and avoiding the Steam SSeS tially subdivided state, is fed into a pressure above referred Furthermore the P d f 10 chamber or gun to which is admitted high presthe improved Process is u ri r in at its quality sure elastic fluid or fluids, for example, steam, is more uniform than that f t produ of a air or other gas, or steam followed by air or discontinuous intermittent p other gas, such treatment being followed by Incidental t0 t us f this i p v d pr ss rapid discharge of the material from the presis the fact thatthe wood chips or other material 15 sure chamber into a region of relatively reduced which are being fed into the gun Pressure pressure, with resulting liberation of pressure. chamber r j c d to suffici n me hani l In U. s. Patents Nos. 1,578,609 dated March 30, p r to overcome the pr s f th t m 1926 and 1,586,159 dated May 25, 1926, I disclose within such chamber plus frictional resistance of and broadly claim such process and apparatus, the material, so that the mechanical pressure to 20 In the patented apparatus, the gun is in the Which the material is Su j y be y form of a cylinder which has a suitable feed g at. opening for receiving a charge of wood chips or Such compression of the material expresses other material, preferably in partially subdivided therefrom as liquid a large quantity of the moisstate. After the gun has been so filled, the openture content, together with other expressible sub- 25 ing is closed and high pressure steam (or other stances including water solubles, resins, gums so elastic fluid) is admitted to the cylinder. After etc., and causes the chips to absorb steam more a short time a discharge port is opened and the readily and heat up more rapidly and evenly material is forced out by the steam and as soon as after they have been forced into the steam presit emerges from the cylinder it is disintegrated sure chamber. The expressed material in some 00 into fibre by the expansion of the steam within cases comes out partly as vapor by reason of its pores and interstices. the high temperature of the material due to In using such apparatus the pressure cylinder preliminary heating, friction and compressing. should be substantially emptied before being re- The compression also makes the chips more C d With a al to be treated, in order to uniform in water content, since the wet chips e5 p v ve t t f at remaining in lose water and the very dry chips probably gain the u after a p v disehergewater during the period of mechanical compres- In operating under this patent, I have cusi n, tomarily used steam at a pressure of 1000 lbs. per By reason of the above facts, all of the chips qo and have had a considerable Waste are rendered practically uniform as regards pene- 40 of steam due to the fact that the high pressure t m by steam and i of temperature st a is pt t d on du t d sc a e a caused thereby, and the resulting product is in vuntil the Sound Of Steam escaping from the consequence of very uniform and superior quality. charge opening has acted as a signal to the oper- Thequality and quantityofproduct may be conator the gun has been emptied of material, trolled or changed by arying the amount of ma 45 whereupon he shuts off the steam. Obviously terial supplied to the pressure feeding means for steam at such high pressurees p during Such unit of time, the pressure of steam in thesteam Interval Wlth enormous rapldltypressure chamber, and the length of time that There h been a further less of steam by reathe chips are subjected tohigh pressure steam. son of the fact that sometimes the steam blows By reason of t fact th t t t t is aways 00 out only the material in or near its dir ct path open during normal operation, so that steam is and leaves some material at sides, so t i discharged from the steam pressure chamber in h be n necessary to admit and discharge steam a continuous and steady stream, it becomes pracmere than Once in Order to empty-the 8 ticable to use the discharged or exhaust steam for Another steam loss has occurred by reason 01' other purposes.

55 the fact that the successive gun discharges are Th invention also contemplates the continuous preheating of the chips or other raw material, preferably by means of steam, and the continuous supplying of the pressure feeding means with such preheated material.

The invention also comprises such modifications of procedure and details of construction as are hereinafter disclosed and claimed.

Reference is hereby made to the accompanying drawings, of which Figure 1 is a vertical longitudinal section of an apparatus suitable for carrying on the improved process;

Fig. 2 is a plan of the apparatus of Fig. 1, partly in section;

Fig. 3 is an enlarged detail of Fig. 1;

Fig. 4 is a section on line 44 of Fig. 3;

Fig. 5 is a side view, partly in section, showing means for continuously separating and condensing exhaust steam; and

Fig. 6 is a side view showing a modified form of apparatus for condensing the exhaust steam.

The gun which contains the pressure chamber is in the form of a horizontal cylinder 1 having a steam supply pipe 10. with control valve or throttle 1d and a pressure gauge 11). The pipe 1a has a similar gauge 1c. A water inlet or supply pipe 1e with control valve 1} is also provided.

The cylinder 1 is formed with an integral flange 2 at each end and a depending branch 3. The branch 3 is provided with an integral flange 4. A hopper-shaped member 5 having top and bottom flanges 6 and 7 respectively is secured to the flange 4 by means of bolts, as shown. A valve block 8 having a flange 9 is bolted to the flange '7. This block is formed with a vertical bore 10 and a tapered discharge outlet 11 having an axis at right angles thereto. A discharge pipe 12 is threaded in the bore 13 of the discharge outlet and communicates with a large pipe 12a for carrying away the discharged material.

The pipe 12a preferably leads to a cyclone separator 12b of well-known construction, Fig. 5. which has a lower outlet 12c for the disintegrated material and a pipe 12d forming an outlet for the exhaust steam. The pipe 12d leads to a condenser of any desired type as for example a water jet condenser 12c having water supply pipes 12g and an outlet 12f.

Instead of the cyclone separator and condenser, Fig. 5, the structure shown in Fig. 6 may be employed. In this device the pipe 12a is connected to the nozzle 80 of a barometric condenser of known construction. The vertical pipe 82 of this condenser is supplied with water by pipe 83 and the pipe 82 discharges the mixture of water and disintegrated material into the tank 84, the contents of which are maintained at a proper level by a rotary pump 85. The advantage of the use of this device is that the steam is all condensed in the pipe 82 so that the pressure of the discharged or exhaust steam approaches zero instead of atmospheric pressure, and the effective range of steam pressure is increased. The volume of the exhaust steam as its pressure falls below atmospheric pressure increases very greatly.

Within the bore 10 of the valve block 8 is a fixed sleeve 14 having a port ,15 and there is a cup 16 rotatable mounted within said sleeve. A port 17 is formed at the base of the wall of the cup 16 so as to register with the port when the cup is i the position shown in Fig. 3.

Suitable means are provided for operating the cup to open and close the valve, and as shown comprise a vertical shaft 18 secured at its upper end to the cup 16 and carrying at its lower end a worm gear 19. The shaft 18 is journaled in the sleeves 20 and 21 of a stuffing box as shown. A worm 22 is mounted on a'horizontal shaft 23 and engages said worm gear 19, and said shaft 23 is rotatable in bearings carried by the bracket 24 which is secured to the valve block 8. A hand wheel 25 is mounted on the shaft 23.

The rotatable cup 16 is preferably formed with a plurality of ports of different heights each of which may at will be brought into alignment with the port 15, whereby the valve is adapted for operating upon different materials or upon material in which the average sizes of the pieces are different. One of such additional ports is indicated at 26, Fig. 3.

If desired some or all of the additional ports of the cup 16 may be of the same size as the port 1'7 so that in case the last named port becomes undesirably worn another port of the same original size may be brought into operative relation with respect to the fixed port 15.

The sleeve 14 is also by preference provided with additional ports 15a, one of which may be the same size as the port 15 and another of a different size, with the same advantages as in the case of the cup 16.

Indicating means are provided for showing the position of the rotatable valve cup 16, and I have shown for this purpose a pointer 27 which is secured at one end to the worm gear 19. The free end of the pointer is provided with an arrow 29 which cooperates with the scale 30 of a fixed plate or sector 28 carried by the bracket 24. The graduations of the scale 30 are preferably marked with suitable indicia for indicating the extent of opening of the discharge ports of the valve members 14 and 16. By means of this device, one may control the consumption or discharge of steam and. by proper selection of port opening secure the best running conditions for securing economy in steam consumption and for obtaining the most desirable quality of fibre, as follows:

It should be noted that the arrangement of the valve ports 15 and 1'? is such as to permit of variation in the width of the discharge opening, which may be anything between zero and the width of the port 1'7. Furthermore by reason of the provision of ports 17 and 26 of different height, one'may by selection of such port vary the height of the discharge opening.

The size of the discharge opening to be used depends upon the size of the chips which are to be fibrated and upon the steam pressure which is used. The opening should be considerably smaller than the largest chip. For example, when running with a steam pressure of 1000 lbs. a chip measuring 2"x1"x% may be forced through a port opening which measures I%"X%,". This is due to the plasticity of the wood under conditions of heat and moisture. The use of a long and. narrow opening is advantageous in preventing clogging and for the fibration of small chips. As a rule the smaller the average size of chip the narrower should be the opening. The opening may in starting the process be made larger than necessary and during the operation its area may be reduced by moving the arm 2'7 until the area at a minimum to permit passage of chips of the average size or grade of those under treatment.

In operating, the cup 16 should be turned to a position to form an opening of the minimum width suitable for use with chips of the size which are to be treated.

The opening of the valve causes an eiflux of steam and material and a fall in the pressure of the steam within the gun, so that the gauge 11) registers a lower pressure than the gauge which difference may, for example, be 50 lbs. per sq. in. Such condition is normal during the carrying on of the process." However a chip of abnormal size upon reaching the discharge opening of the valve may clog the same, in which case the pressure quickly builds up within the gun so that the gauge 1b reads the same as the gauge 10. In such case the operator is thereby warned that the valve opening is clogged, whereupon he moves the arm 27 in the proper direction to increase thesize of the discharge opening.

The effect of such increase of area of opening is to cause the same to become unclogged, whereupon the gauge 15 returns to or below normal position and the operator then returns the arm 27 to its former position.

Steam economy may be effected by shifting the arm 27 to a running position in which the area of the discharge opening is at a minimum consistent with the substantial avoidance of clogging. Such position may vary with different kinds of material even though the average sizes of pieces are the same, but can readily be ascertained by trial.

Referring now to the means for supplying raw material to the pressure chamber of the gun 1, Figs. 1 and 2, the material in the form of wood chips or other ligno-cellulose bodies is continuously supplied to a vertical preheating drum 31 by any suitable conveying means. This drum is open at top and bottom and is mounted on a hollow rotatable shaft 32. The shaft assembly comprises also an interior sleeve 33 having a stuifing box at its lower end to receive a fixed steam pipe 34. The interior of the shaft 32 is in communication with the bores of a plurality of tubes 35 which extend diametrically across the interior of the drum and are secured to the wall thereof at their outer extremities. Each of these tubes is formed with a multiplicity of perforations 36 to permit escape of steam.

In order to supply steam to the drum 31 for the preheating of the chips, a pipe 129! may be connected at one end to-the pipe 12d and at the other end to pipe 34. A valve 12h controlled by a weight may be used to maintain sufficient pressure in pipe 12d to cause any desired proportion of the steam which enters pipe 12d to flow through pipe 12g then through the chips in drum 31.

The hollow shaft 32 is supported on a thrust roller bearing 37 carried by a fixed support 38 and a sleeve 39 is rigid with the shaft. The lower end of said sleeve is provided with a worm gear 40 driven by any suitable means, as for example, an electric motor;

The upper end of the sleeve 39 is provided with a horizontal flange and above the sleeve is a plate 46 secured to shaft 32. A table 47 is secured to said flange and plate. Immediately above the table is a plow 48 secured at one end to a fixed pin 49 about which it is angularly adjustable. The function of this plow is to remove material from the table and cause it to drop into a hopper 50 thence into the interior of a pressure screw casing.

In many cases the preheating means may be entirely dispensed with, and the raw material fed directly into the opening 52a of the pressure screw casing.

This casing comprises a body 51 and a. removable cover plate 52 bolted thereto. The cover plate is formed with a feed opening 520, which communicates with the hopper 50. The body 51 is formed at one end with a flange 53 and the cover plate with a similar flange 54. A bearing block 55 is bolted to said flanges and is provided with a journal bearing 56 for the shaft 58 of the horizontal pressure screw. A thrust roller bearing 57 is interposed between the bearing block 55 and shaft 58, as shown. The thrust member 59 which is secured to said shaft is grooved to receive a retaining plate 60 which is removably secured to the block 55 by screws.

The horizontal shaft 58 extends beyond the bearing block 55 and is provided with a sprocket 61 which is keyed thereto and may be driven from any suitable source of power. This shaft is provided with a spiral blade or ribbon 62 to enable it to convey and compact the material supplied thereto through the feed opening 520:. The spiral blade turns in a bushing 63 which lines the pressure screw casing. A number of small apertures 63a extend entirely through the body 51 and bushing 63 to permit the escape of water which is expressed from the chips as they are compressed by the action of the pressure screw.

In order to prevent the material which is operated on by the pressure screw from rotating therewith, it is desirable to provide the casing body 51 with a series of stops 6% which are rigid therewith and extend inward into proximity to l the shaft 58, the screw blade or ribbon 62 being cut into sections as shown to enable it to clear the said stops.

The forward end of the body 51 of the pressure screw casing is formed with a flange 65 which i bolted to the flange 2 of the gun. The forward end of the body 51 is formed with a bore within which is a bushing 66.

A. horizontal screw conveyer 67 is mounted within the horizontal portion of the steam pressure chamber. This conveyor may be termed the preheating screw, inasmuch as its length and speed are so designed as to cause the material operated upon to be heated by steam within such chamber for a definite period of time sufficient to enable the steam to thoroughly penetrate and heat the material before it drops into the discharge portion of such chamber.

The forward end of the shaft of the preheating screw is journaled in a bearing carried by the head block 68 and extends thence through a stuffing box 69 to the exterior, at which point a sprocket 70 is mounted thereon for driving the same at any desired speed which may bevaried to secure the best results with different kinds of material treated, as regards quality of fiber produced, etc.

The rear end of the screw conveyor shaft 6'! may be provided with a socket or bearing 71 to receive the end of the shaft 58. If desired, the. screw conveyor 6'7 may be so designed that it may be rigidly united to the shaft 58 and driven thereby, thus dispensing with the drive sprocket 70 and stuffing box 69, and the central opening in the head block 68.

The process may be carried out as follows:

The raw material, preferably wood chips, which have been previously graded as to" size, by means of suitable screens or the like, is continuously fed into the drum 31 which it fills, being supported by the table 47. The drum and table are continuously rotated by suitable means which drives the worm gear 40 and hollow shaft 32. Steam from the pipe 34 enters the bore of the shaft 32 and flows thence through the radial pipes 35 and escapes through the openings 36. The steam heats the chips to a temperature of approximately 212 F. Each of the chips is thus heated as it descends through the drum to the table. As it reaches the table it is brought into contact with the stationary plow 48 and pushed from the table, falling into the hopper 50, thence through opening 52a into the pressure screw casing.

Under some circumstances it is not necessary to heat the material which is fed to the pressure screw. Other means for heating the material may be used if desired. In such case any suitable method of feeding material through the opening 52a. may be employed.

The pressure screw shaft 58 is continuously rotated and causes the material to move forward toward the steam pressure chamber. Such movement is opposed by the steam pressure, with the result that sufficient pressure must be imparted to the material by the pressure screw to overcome such steampressure plus the resistance due to the friction of the material on the pressure screw, casing and stops. .The result of these opposing forces is that the material forms a plug of considerable length within the bushing 66, fresh material being continuously added to the rear of such plug and material being continuously detached from the forward end of the plug and fed along the horizontalportion of the gun I by the preheating screw. The material forming the plug is very dense and acts as combined means for rotatably supporting the shaft 58 and preventing fiow of steam from the steam pressure chamber into the pressure screw chamber. Such plug constantly receives new material from the rear to compensate for material detached from the forward end.

By reason of the great pressure applied to the material by the pressure screw, liquid and/ or vapor is expressed therefrom and is blown out through the orifices 63a. This leaves the chips with a more nearly uniform moisture content.

As the chips enter the steam pressure chamher they expand rapidly and absorb high pressure steam. The preheating screw reduces the compactness of the plug of chips or the like, and carries them forward for a short period which may vary with the steam pressure used, and with the kind of material treated and the class of fibre to be made. With pressures of from 1000 to 600 lbs. per sq. in. I have obtained good results with periods of from two to twelve seconds. This time may be regulated by varying the speed at which the preheating screw is driven. With some materials the steam pressure may be as low as 275 lbs. per sq. in. and it may be 1000 lbs. or higher.

As the chips reach the end of the blade of the preheating screw they fall into the vertical portion of the steam pressure chamber where they are brought into the path of and caught by the rush of escaping steam and forced therewith in a continuous stream through the valve ports 17 and 15, which always remain open during normal operation of the apparatus. As they emerge from said ports into a region of substantial atmospheric pressure viz; pipes 12 and 120., the expansion of the high pressure steam contained within their interstices together with any steam which may be generated from the water content of the chips upon release of pressure instantly and very thoroughly disrupts and explosively disintegrates the chips into a mass of loose' fibres or bundles of fibres. Such mass may if desired be further reduced by beating or refining in a water bath in a manner similar to paper pulp, but for many purposes and with proper regulation of the time interval within the steam pressure chamber and size of discharge port, such beating and refining may be largely and sometimes entirely dispensed with.

With some raw materials and for producing certain grades of fibre it is'desirable to admit water to the pressure chamber of the gun 1. This may be done by opening the valve If to cause a continuous influx of water supplied by a suitable pump. The quantity of water so supplied is small as compared to the quantity of material treated. The fibres produced from wood chips when water is so admitted seem to be softer and longer than when water is not used.

Among the advantages of the invention are the following:

By reason of the removal of water from the chips in the pressure screw chamber they enter the steam pressure chamber with a diminished and low water content and are substantially alike or uniform with respect to such content. In consequence of their low water content they are more readily and quickly penetrated and heated by the steam, and since they are substantially uniform in this respect, the product is of a very uniform character.

By reason of the high mechanical pressure to which the chips are subjected before entering the steam pressure chamber, their pores and interstices have been largely emptied of air and liquid so that as they leave the zone of mechanical pressure and enter the steam pressure chamber and expand by reason of their elasticity, a partial vacuum is formed in their interstices whereby the influx of steam is facilitated.

By reason of the continuity of the process each chip is subjected to the action of the steam in the pressure chamber for a definite and equal period of time, thus favoring the production of fibre of maximum uniformity.

Saving of steam is effected in several ways.

(1) The reduction of the water content of the chips prior to' their entrance into the steam chamber results in a smaller steam consumption since less steam is required for preheating and for exploding the chips. (2) The continuity of the process avoids the steam loss of the intermittent process due to the escape of steam from the gun after the material has been blown out and before the steam is shut off, and the additional loss of a gun full of steam which escapes through the discharge port after the steam has been shut of. (3) The continuity of the process avoids the steam loss of the intermittent process caused by the necessity of sometimes re-admitting steam to the gun and discharging same to remove material not removed by the prior or main discharge operation.

Heat units are saved or conserved by the present process as compared with the intermittent process by reason of the fact that the temperature of the steam pressure chamber is substantially constant instead of varying, for example, 140 from the temperature of steam at 1000 lbs. pressure to the temperature of steam at atmospheric pressure.

Additional heat units are saved by reason of the fact that in the present process the discharged steam is in the form of a continuous current whereby it becomes practicable to apply its heat units to useful purposes in either condensed or uncondensed form.

By reason of the continuity of the process 150 many hand operations are dispensed with, thus tending downwardly therefrom,

reducing labor cost.

The conditions to which the material is subjected are more uniform throughout the entire process than in a discontinuous or intermittent scope of the appended claims are also included within my invention.

I claim:

1. The process of disintegrating porous material which comprises maintaining an inclosed body of high pressure steam, forcing into said body material to be disintegrated, continuously discharging therefrom into a low pressure region steam and such material, continuously separating such discharged steam and disintegrated material, and condensing said steam.

2. In a process for continuously feeding solid material through an orifice into a chamber in which a high fluid pressure is maintained, subdividing the material into small pieces and compacting the same into a plug having a cross section corresponding in shape and size to the oriflee, using said plug to maintain closure of said orifice and to prevent escape of fluid from said chamber, and continuously compacting new material against the rear end of said plug with sufficient force to cause the forward end to continuously progress through said orifice.

3. The process of disintegrating ligno-cellulose material which consists in subdividing the material into small pieces, softening the same by heat and moisture, maintaining a body of steam at a pressure exceeding 275 lbs. per square inch, continuously forcing the softened pieces into said body of steam and continuously discharging from said body into a low pressure region a stream of steam and material. I

4. In an apparatus of the class described, a body having a high pressure chamber, an inlet forelastic fluid, pressure means for forcing material into said chamber, a constricted discharge port open for escape of material, and means for controlling the area of said port.

5. In an apparatus of the class described, a body having a high pressure chamber, an inlet for elastic fluid, pressure means for forcing material into said chamber, a constricted'discharge port open for escape of material, means for controlling the area of said port, means for separating elastic fluid from disintegrated material, and means for condensing such fluid.

6. A body having a high pressure chamber with a horizontal portion and a vertical portion extending downwardly therefrom, said vertical portion being provided with a constricted discharge opening, pressure means for feeding material'into said horizontal portion, and means for causing material to fall from the horizontal portion into the vertical portion.

7. A body having a high pressure chamber with a horizontal portion anda vertical portion exsaid vertical portion being provided with a constricted discharge opening, pressure means for feeding material into saidhorizontal portion, means for causing material to fall from the horizontal portion into the vertical portion and means for varying the time interval between the entrance and exit of given material into and out of the horizontal portion of the pressure chamber.

8. In an apparatus of the class described, a body having a pressure chamber and a discharge opening, and means for controlling the escape of material through said opening comprising a movable member having ports of different size so situated as to selectively register with said discharge opening upon movement of said member.

9. In an apparatus of the class described, a body having a pressure chamber, and valve means therefor comprising a member having a port and a co-operating member having a plurality of ports so arrangedthat by relative movement of said members the port of one may register with either of the'ports of the other.

10. The apparatus of claim 9 in which the plurality of ports are of equal size.

i 11. The apparatus of claim 9 in whichthe plurality of ports are of unequal size.

12. In an apparatus of the class described, a body having a pressure chamber, and a valve for controlling the escape of fluid therefrom, said valve comprising a member having a plurality of ports, and means for closing and opening one of said ports, said member being adjustable to bring any one of said ports into alignment with said closing means.

13. In an apparatus of the class described, a body having a pressure chamber and a discharge opening, means for controlling the escape of material through said opening comprising a hollow rotary member having ports of different size so situated as to selectively register with said discharge opening ,upon movement of the rotary member, and means for rotating said member.

14. In an apparatus of the class described, a body having a pressure chamber and a discharge opening, means for controlling the escape of material through said opening comprising a member having ports of different size so situated as to selectively register with said discharge opening upon movement of saidmember, and indicating means to show the relative positions of the discharge opening and of said ports.

15. The process of claim 3 in which steam discharged from the body of steam is used for heating and softening the pieces of material.

16. The process of claim 1 in which the steam is condensed in a region in which the pressure is substantially below atmospheric pressure.

17. Continuous explosion process of disintegrating porous material in partially subdivided state, which comprises continuously supplying elastic fluid under high pressure into a chamber having a constricted outlet open during normal operation to a region of relatively reduced pressure, continuously forcing said material into the chamber against the high pressure therein, and bringing same into the path of the elastic fluid moving to the open outlet, whereby the material issues continuously with the fluid and is explosively disintegrated upon issuance.

18. Process as in claim 17, in which the porous material is fibrous vegetable material.

19. Process as in claim 17, in which the porous material is wood-chips.

20. Process as inclaim 17, in which the elastic fluid is steam.

21. Process as in claim 17, in which the elastic fluid is steam, and the steam and the material being disintegrated are separated and the steam saved.

22. Process as in claim 17, in which the pressure in the chamber is materially in excess of 275 pounds per square inch.

23. Process as in claim 17, in which the elastic fluid is steam, and in which the pressure is materially in excess of 2'75 pounds per square inch.

24. Process as in claim 17, in which the material to be disintegrated upon being introduced into the chamber is dropped down upon the outlet. i

25. Process as in claim 17, in which the subdivided material is forced in by screwing, and held against rotation while being screwed in.

26.. Process as in claim 17, in which the subdivided material is forced in by screwing, and is thereby compacted, and is decompacted within the chamber prior to being brought into the path of outgoing fluid.

27. Process as in claim 1'7, in'which the relative rates of supply of elastic fluid and of material to be disintegrated are such as to maintain a reserve quantity of the subdivided material in the chamber adjacent to the open outlet.

28. Process as in claim 17, in which the liquid is expressed out of and separated from the subdivided material in the course of forcing same into the chamber.

29. Process as in claim 17, in which water is supplied to the chamber against the pressure therein.

30. In apparatus for the explosive disintegration of porous material, such as wood-chips, a. body having a pressure chamber provided with an outlet which is open during normal operation, means for supplying to said chamber elastic fluid under high pressure, means for forcing porous material into said chamber against the pressure therein, and means comprising indicator mechanism for varying the area of said open outlet, whereby the rate of discharge can be manually controlled during operation so as to maintain a supply of chips within the chamber and behind the open outlet, and thereby avoid free discharge of the elastic fluid without obtaining adequate output of the subdivided material therewith.

31. In apparatus for the continuous explosive disintegration of fibrous material such as woodchips and the, like, a body having a pressure chamber, means for supplying thereto elastic fluid under high pressure, an outlet for said chamber always open during normal operation, and screw means for forcing into the chamber against the pressure therein a supply of subdivided mate- I' rial to be disintegrated, said forcing means comprising screw means producing an advance movement of the subdivided material, and also comprising means for preventing rotation of the subdivided material, while being screwed forward.

WILLIAM H. MASON. 

